Scientists have just got their hands on the toughest material ever recorded, which has properties that could be immensely useful in various applications. The discovery was made by scientists from Lawrence Berkeley National Laboratory (Berkeley Lab) and Oak Ridge National Laboratory as they inspected an alloy consisting of chromium, cobalt, and nickel (CrCoNi).
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What has astonished scientists the most — and provided hope for the alloy’s varied potential usage — is the fact that the alloy is highly ductile while being the toughest material ever recorded.
Ductility is a material’s ability to be shaped into various forms. Another feature of the CrCoNi alloy is that, unlike other materials that tend to lose their strength over a period of time, this alloy gains strength as it gets colder.
The groundbreaking study was published in Science. The researchers wrote that “CrCoNi-based medium- and high-entropy alloys display outstanding damage tolerance, especially at cryogenic temperatures”.
Easo George, project co-lead and Governor’s Chair for Advanced Alloy Theory and Development at ORNL and the University of Tennessee, stated that the material used for structural design required to be not just strong but also ductile and fracture resistant.
“Typically, it’s a compromise between these properties. But this material is both, and instead of becoming brittle at low temperatures, it gets tougher,” he was quoted as saying by Phys.org.
CrCoNi is classified as a high entropy alloy (HEAs). Alloys used in the industry typically have a dominant amount of one element combined with smaller levels of others. HEAs, on the other hand, have equal proportions of each element, allowing them to be both exceedingly strong and ductile.
Researcher Robert Ritchie, a senior faculty scientist at Berkeley Lab’s Materials Sciences Division and the Chua Professor of Engineering at UC Berkeley, said CrCoNi had a toughness of 500 megapascals square root meters at near liquid helium temperatures (20 Kelvin, -424 Fahrenheit).
“In the same units, the toughness of a piece of silicon is one, the aluminum airframe in passenger airplanes is about 35, and the toughness of some of the best steels is around 100. So, 500, it’s a staggering number,” she said.
The era of space exploration is gathering immense pace and humankind’s desire to go further into the universe is burning brighter than ever. Entrepreneurs like Elon Musk and space programs like NASA’s are seriously contemplating setting up human colonies on Mars. But as we move deeper into the universe and away from the Sun, it begins to get very, very cold, and traditional material used to erect structures on Earth might not stand a chance in such alien environments.
Discoveries like CrCoNi, therefore, give hope to scientists for possibly having the means to build structures and machines that could travel farther to collect crucial data and information and survive in extreme environments the universe is well capable of producing.
While the discovery has charged the scientists up, they understand that cobalt and nickel are already in short supply owing to their widespread use in batteries. The scientists now plan to focus their attention on forming alloys using more abundant elements and hopefully have them display similar properties of strength and ductility.
The researchers do admit that real-world use might still be years away, as structure materials need to be studied for years to understand their behavior in various conditions. However, the breakthrough does offer a guiding light for scientists to keep moving forward. May they find more ‘strength’ in the materials they study in the days ahead!